Study of a Pump as Turbine for a Hydraulic Urban Network Using a Tridimensional CFD Modeling Methodology

This paper presents a computational fluid dynamics (CFD) modeling methodology that has been developed to provide predictions of very local heat transfer variation in fuel rod assemblies. Results from the CFD analysis are used in HIDUTYDRV and other advanced codes that have been developed and are used internally by Westinghouse to predict very local crud deposition and dryout. This methodology is used in making the EPRI Level IV crud and corrosion guideline assessments, which were developed in response to the INPO 0 by 2010 initiatives. This methodology has been in production use for risk assessment of CE-design 14×14 and 16×16 fuel reloads. The methodology is in the process of being extended to other Westinghouse fuel design reloads. Local crud deposition and dryout are strongly dependent on very local boiling or steaming on small areas of the fuel rod, often referred to as local hot spots. These local hot spots can not be predicted utilizing standard subchannel modeling methodology because subchannel models do not provide sufficient azimuthal detail of individual rods. Local hot spots are also very dependent on the particular grid features, which are not explicitly modeled in subchannel analysis. The commercial code Star-CD by CD-ADAPCO is utilized to develop a detailed CFD model of a single fuel assembly grid span. Detailed azimuthal and axial predictions of the heat transfer coefficient are made for each rod in the model. These predictions are then normalized to a Dittus-Boelter based heat transfer coefficient so that the predictions can be translated to other spans and other fuel assemblies. Details of this translation as well as the use of normalized heat transfer coefficients in the advanced codes used to predict local crud and dryout are provided in a separate follow-on paper ICONE17-75715 also being presented at ICONE17. This paper presents details on the CFD methodology that has been developed to predict local normalized heat transfer coefficients for a fuel rod assembly. Results for a particular application are provided to illustrate the methodology. The application is for a fuel design that contains mixing grids and spans with and without intermediate flow mixers.

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Refinement of the characteristics of the aerodynamic resistance to the movement of special wheeled chassis and tractors based on the use of computational gas dynamics methods

Nauchno-tekhnicheskiy vestnik Bryanskogo gosudarstvennogo universiteta ◽

10.22281/2413-9920-2021-07-03-270-279 ◽

2021 ◽

Vol 7 (3) ◽

pp. 270-279

Author(s):

V.I. Tarichko ◽

◽

P.I. Shalupina ◽

Keyword(s):

Gas Dynamics ◽

Aerodynamic Drag ◽

Aerodynamic Resistance ◽

Cfd Modeling ◽

Modeling Methodology ◽

Calculation Results ◽

Aerodynamic Drag Coefficient ◽

Wheeled Vehicles ◽

Selection Of ◽

Preliminary Selection

An accurate assessment of the characteristics of the aerodynamic resistance to movement is important for the preliminary selection of the parameters of the engine, transmission and chassis of a special wheeled chassis or tractor. The strength of the movement resistance affects the dynamic characteristics of the car. The existing calculation methods allow for a wide variation of the aerodynamic drag coefficient, which complicates the task of preliminary selection of car parameters. The purpose of this article is to clarify and develop the engineering methodology for carrying out traction-dynamic calculations of special wheeled vehicles and tractors based on the results of computer modeling performed using computational fluid and gas dynamics (CFD modeling) methods. The modeling methodology and calculation results of a special wheeled chassis manufactured by JSC «BAZ» are considered.

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A Three Dimensional CFD Modeling Methodology Applied to Improve Hydraulic Components Performance

Energy Procedia ◽

10.1016/j.egypro.2015.11.849 ◽

2015 ◽

Vol 82 ◽

pp. 950-956 ◽

Cited By ~ 1

Author(s):

Emma Frosina

Keyword(s):

Three Dimensional ◽

Cfd Modeling ◽

Modeling Methodology

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Two-Phase CFD Study of Coolant through a 5×5 Rod Bundles with Grid Spacers

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.444-445.529 ◽

2013 ◽

Vol 444-445 ◽

pp. 529-533

Author(s):

Shen Gen Tan ◽

Song Wei Li ◽

Yong Jun Jiao ◽

Qing Lu ◽

Guo Bin Wang ◽

...

Keyword(s):

Flow Field ◽

Two Phase Flow ◽

Size Group ◽

Cfd Modeling ◽

Transfer Model ◽

Phase Flow ◽

Rod Bundles ◽

Two Phase ◽

Pressurized Water ◽

Modeling Methodology

A numerical study using computational fluid dynamics (CFD) under air/water two-phase flow condition without thermal transmission is carried out utilizing the commercial CFD code CFX. A detailed geometry of 5×5 rod bundles with two grid spacers in the Pressurized Water Reactor (PWR) is set up for analyzing. The Multiple Size Group (MUSIG) model based on the population balance equation is employed to describe the characteristic of flow field in which the dispersed phase has a large variation in size, and the breakup and coalescence interaction among different sizes of the bubbles. The effects of the size fraction at inlet, the size group quantities, the breakup and coalescence coefficients, the momentum transfer model, and so on, are studied. The results demonstrate that various parameters and two-phase model have different impacts on the analysis results. The detailed CFD modeling methodology for two-phase flow conditions in PWR fuel assemblies is developed according to the above-mentioned investigations. The flow field patterns and air/water phase distributions in the computational results shows that the two-phase modeling methodology in the present work is reasonable.

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Recovery boiler sootblowers: History and technological advances

TAPPI Journal ◽

10.32964/tj14.1.51 ◽

2015 ◽

Vol 14 (1) ◽

pp. 51-60

Author(s):

HONGHI TRAN ◽

DANNY TANDRA

Keyword(s):

Cfd Modeling ◽

Computing Systems ◽

The Past ◽

Technological Advances ◽

Recovery Boilers ◽

Computational Fluid Dynamics Cfd ◽

Recovery Boiler ◽

Steam Parameters ◽

Insight Into ◽

Deposit Removal

Sootblowing technology used in recovery boilers originated from that used in coal-fired boilers. It started with manual cleaning with hand lancing and hand blowing, and evolved slowly into online sootblowing using retractable sootblowers. Since 1991, intensive research and development has focused on sootblowing jet fundamentals and deposit removal in recovery boilers. The results have provided much insight into sootblower jet hydrodynamics, how a sootblower jet interacts with tubes and deposits, and factors influencing its deposit removal efficiency, and have led to two important innovations: fully-expanded sootblower nozzles that are used in virtually all recovery boilers today, and the low pressure sootblowing technology that has been implemented in several new recovery boilers. The availability of powerful computing systems, superfast microprocessors and data acquisition systems, and versatile computational fluid dynamics (CFD) modeling capability in the past two decades has also contributed greatly to the advancement of sootblowing technology. High quality infrared inspection cameras have enabled mills to inspect the deposit buildup conditions in the boiler during operation, and helped identify problems with sootblower lance swinging and superheater platens and boiler bank tube vibrations. As the recovery boiler firing capacity and steam parameters have increased markedly in recent years, sootblowers have become larger and longer, and this can present a challenge in terms of both sootblower design and operation.

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Technical Cost Modeling Methodology for Novel Manufacturing

10.33599/nasampe/s.19.1490 ◽

2019 ◽

Author(s):

Robin Glebes ◽

Joshua Dustin ◽

Jan-Anders Mansson

Keyword(s):

Cost Modeling ◽

Modeling Methodology ◽

Technical Cost

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CFD Modeling of Film Cooling Flow with Inclined Jets

Journal of Advances in Applied & Computational Mathematics ◽

10.15377/2409-5761.2016.03.01.5 ◽

2016 ◽

Vol 3 (1) ◽

pp. 29-33

Author(s):

Majid Almas ◽

Keyword(s):

Film Cooling ◽

Cfd Modeling ◽

Cooling Flow

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WET BURNING – THE MODERN TREND IN ENVIRONMENTAL BENIGN FUEL COMBUSTION AND IN SOLUTION TO THE PROBLEM OF SUSTAINABLE DEVELOPMENT OF THE POWER GENERATION

Alternative Energy and Ecology (ISJAEE) ◽

10.15518/isjaee.2018.25-30.096-117 ◽

2018 ◽

pp. 96-117 ◽

Cited By ~ 2

Author(s):

B. S. Soroka

Keyword(s):

Numerical Simulation ◽

Nitrogen Oxides ◽

Chemical Kinetics ◽

Fuel Combustion ◽

Transport Processes ◽

Cfd Modeling ◽

Furnace Chamber ◽

Modern Trend ◽

Atmospheric Air ◽

No Formation

The article considers the role and place of water and water vapor in combustion processes with the purpose of reduction the effluents of nitrogen oxides and carbon oxide. We have carried out the complex of theoretical and computational researches on reduction of harmful nitrogen and carbon oxides by gas fuel combustion in dependence on humidity of atmospheric air by two approaches: CFD modeling with attraction of DRM 19 chemical kinetics mechanism of combustion for 19 components along with Bowman’s mechanism used as “postprocessor” to determine the [NO] concentration; different thermodynamic models of predicting the nitrogen oxides NO formation. The numerical simulation of the transport processes for momentum, mass and heat being solved simultaneously in the united equations’ system with the chemical kinetics equations in frame of GRI methane combustion mechanism and NO formation calculated afterwards as “postprocessor” allow calculating the absolute actual [CO] and [NO] concentrations in dependence on combustion operative conditions and on design of furnace facilities. Prediction in frame of thermodynamic equilibrium state for combustion products ensures only evaluation of the relative value of [NO] concentration by wet combustion the gas with humid air regarding that in case of dry air – oxidant. We have developed the methodology and have revealed the results of numerical simulation of impact of the relative humidity of atmospheric air on harmful gases formation. Range of relative air humidity under calculations of atmospheric air under impact on [NO] and [CO] concentrations at the furnace chamber exit makes φ = 0 – 100%. The results of CFD modeling have been verified both by author’s experimental data and due comparing with the trends stated in world literature. We have carried out the complex of the experimental investigations regarding atmospheric air humidification impact on flame structure and environmental characteristics at natural gas combustion with premixed flame formation in open air. The article also proposes the methodology for evaluation of the nitrogen oxides formation in dependence on moisture content of burning mixture. The results of measurements have been used for verification the calculation data. Coincidence of relative change the NO (NOx) yield due humidification the combustion air revealed by means of CFD prediction has confirmed the qualitative and the quantitative correspondence of physical and chemical kinetics mechanisms and the CFD modeling procedures with the processes to be studied. A sharp, more than an order of reduction in NO emissions and simultaneously approximately a two-fold decrease in the CO concentration during combustion of the methane-air mixture under conditions of humidification of the combustion air to a saturation state at a temperature of 325 K.

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